Workpiece support device

Abstract

A workpiece support device including a base, an electrically conductive worktable rotatably supported with respect to the base, a motor, a reducer that transmits rotation of the motor to the worktable and reduces a speed of the rotation, and a metal adapter interposed between the worktable and the reducer to separate the worktable and the reducer from each other. The worktable and the adapter are electrically insulated by an insulating coating film formed by a surface treatment on a surface of the worktable or the adapter.

1 . A workpiece support device comprising:
 a base;   an electrically conductive worktable rotatably supported with respect to the base;   a motor;   a reducer that transmits rotation of the motor to the worktable and reduces speed of the rotation; and   a metal adapter interposed between the worktable and the reducer to separate the worktable and the reducer from each other,   wherein the worktable and the adapter are electrically insulated by an insulating coating film formed by a surface treatment on a surface of the worktable or the adapter.   
     
     
         2 . The workpiece support device according to  claim 1 , wherein
 the adapter has a ring shape and is interposed between an annular flange surface of the reducer and an annular flange surface of the worktable,   the adapter has a contact surface that contacts the worktable and that is provided with the insulating coating film, and   the adapter has a plurality of through holes through which bolts that fasten the worktable and the reducer are inserted, and   wherein the worktable and the reducer are fastened together by the bolts with insulating washers having electrical insulating properties.   
     
     
         3 . The workpiece support device according to  claim 2 , wherein
 through holes into which the bolts are inserted and counterbores in which heads of the bolts are disposed are formed in one of the worktable and the reducer,   screw holes in which the bolts are tightened are provided in the other one of the worktable and the reducer, and   the insulating washers are interposed between seating surfaces in the counterbores and the heads of the bolts.   
     
     
         4 . The workpiece support device according to  claim 3 , wherein the through holes in the worktable or the reducer and parts of outer peripheral surfaces of the bolts that are inserted into the through holes or inner peripheral surfaces of the through holes are covered with a coating containing an electrically insulating material or with an insulating coating film. 
     
     
         5 . The workpiece support device according to  claim 1 , wherein
 the motor is fixed to the base, and   the motor and the base are electrically insulated from each other by an electrically insulating material.   
     
     
         6 . The workpiece support device according to  claim 1 , wherein
 the motor and the reducer are each equipped with a toothed gear that transmits rotations of the motor, and   an insulating coating film is formed by a surface treatment on a surface of the toothed gear of the motor.